In that case, my dad's favorite expression is "beggars can't be choosers." Do you have any other prospects? If so, as difficult as it is, my advice is to sit tight for a few weeks and wait to see if anything else comes in.
If not, did you receive ANY need-based aid? If so, all you can do is ask for a reconsideration of your EFC. If not, or if that fails, welcome to the club! If the school is the one I am thinking of, no, they are not known for great aid for most people, because they try to spread it around and give something to everyone.
Med school is insanely expensive, but the good news is that you are going to be a doctor, are going to be able to borrow every penny you reasonably need, and will have a sufficient income in the future to pay it all back, with interest. It will suck, but you are good to make a decent income and have a very decent life. CONGRATULATIONS!!!!